Succedssful launch for third Inmarsat 4 Satellite 19th August 2008 ? Inmarsat (LSE:ISAT), the leading provider of global mobile satellite communications services, has confirmed the successful launch and acquisition of the third Inmarsat4 satellite. The satellite was launched on a Proton Breeze M rocket from the Baikonur Cosmodrome in Kazakhstan at 11.43pm BST on 18th August (4.43am 19th August, local time). Inmarsat?s tracking station in Fucino, Italy was able to track the satellite while it was still coupled to the Breeze M launch vehicle. Launch provider ILS confirmed successful spacecraft separation at 8.46am BST on 19th August. The satellite is the third in the I4 constellation, concluding a decade of development and a $1.5 billion investment. The current constellation of two Inmarsat4 satellites delivers mobile broadband services to 85 per cent of the world?s landmass, covering 98 per cent of the world?s population. The third I4 will complete the global coverage for Inmarsat?s broadband services. Andrew Sukawaty, CEO and Chairman of Inmarsat, said: ?The Inmarsat4s are the world?s most sophisticated commercial network for mobile voice and data services, and the successful launch of the third I4 allows us to complete the global coverage for our broadband services. Once the third I4 is operational, Inmarsat will have the only fullyfunded nextgeneration network for mobile satellite services.? The Proton Breeze M is one of the few launch vehicles capable of lifting the I4 satellite ? the size of a London doubledecker bus and weighing six tons ? into geostationary transfer orbit. The I4 F3 satellite will now undergo a period of deployment and several weeks of comprehensive tests and manoeuvres before being positioned in geostationary orbit at 98? West. Inmarsat satellites are currently relied on by the world?s shipping, oil exploration, defence and aviation industries to service their communications needs. Inmarsat is also the communications channel of choice for the media when reporting from the world?s danger zones and for NGOs, government agencies and the United Nations when coordinating rescue efforts. About Inmarsat Inmarsat plc (LSE: ISAT) is the leading provider of global mobile satellite communications.Since 1979, Inmarsat has been providing reliable voice and highspeed data communications to governments, enterprises and other organisations, with a range of services that can be used on land, at sea or in the air. The company?s services are delivered through a global network of more than 500 distribution partners and service providers operating in 180 countries. For the year ended 31 December 2007, Inmarsat plc had total revenue of US$576.5 million.